Tree Tobacco (Nicotiana glauca) heralds from South America, but in Hawaii, it’s an invasive species. The chances of eradicating it are slight. Controlling its spread is a more realistic possibility. But tree tobacco is one invasive species in Hawaii that does have something going for it.
Enter Blackburn’s sphinx moth (Manduca blackburni), a large, endemic moth, once thought extinct, and a long-time resident on the endangered species list. Among its problems is that its host species, ‘aiea, (Nothocestrum spp.) has been on the decline for a while. ‘Aiea belongs to the nightshade family (Solanaceae) as does tree tobacco.
It seems that the moth, in the interests of survival, decided tree tobacco is not so bad. So we have an endangered species becoming reliant on an invasive species. Hmm. As I said, control is the most likely approach with tree tobacco and that will undoubtedly involve checking to see whether Blackburn’s sphinx moth is present before removing areas of tree tobacco.
That’s good news for the plant in this photo. I found it at Pu’u Wa’awa’a, a State Forest Reserve on the northern slope of Hualalai. Pu’u Wa’awa’a is home to a variety of endangered plants and animals including Blackburn’s sphinx moth.
Tropical Storm Darby reached the Big Island yesterday. It was due to pass over this corner of the island during the night. The predicted track followed the north coast and since it was packing 60 knot winds on its approach, storm warnings were issued.
The power went out here Friday, getting the jump on the storm, but luckily it was just for an hour or so. Saturday dawned dark and windy with sudden, intense downpours, but in the early afternoon the weather broke for a short while and I went down to the coast to see how things looked. In truth, while it was very windy, it didn’t look that much worse than it often does around here.
On the way back from a short walk, some movement caught my eye. A large bird angling along the coast. Then another. In all, three great frigatebirds headed east, into the teeth of the storm. They made slow progress, sliding toward the coast, then away. Even though it was slow going, their progress looked effortless. They glided on the air currents, beating their wings only occasionally. The nice thing about their slow progress was that they remained in view for some time.
Returning home, the power was out again, but as the afternoon progressed the winds died to nothing (the storm had tracked farther south than anticipated). The early evening was tranquil enough that when I stepped outside, mosquitoes quickly buzzed around me. Mosquitoes do not do tropical storms.
Around 8:30 in the evening a decision needed to be made. Power had been out for seven hours or so and the contents of the refrigerator weren’t likely to last the night. It was time to pack the essentials into a cooler while trying not to lose whatever cold air survived in the fridge.
A smooth, military-style operation was worked out. Doors opened, items whisked from shelf to cooler, ice blocks rearranged. The operation was a success. I snapped the lid down on the cooler and the exact instant I did so, the microwave beeped and the power returned.
Yesterday, I posted about my hike into Waipi’o Valley. One feature of the valley is that wild horses live there. These appear to be ‘wild’ in the sense that they aren’t owned, but they’re not the wild mustangs of the wide open west.
I saw the first of them when I came to this large lake spanning the sandy road leading to the beach. At first I didn’t notice it, but as I looked for my best path around the pond, I saw it standing off to the side, by the trees. My best path would take me in the horse’s direction; the other side looked too muddy.
I looked at the horse again. It hadn’t moved. Not at all. Not a swish of the tail, not a flick of an ear. It was eerily still, so still I wondered for a moment if it wasn’t a super-realistic, life size model set there to disconcert tourists. No matter. I had to go by it and it would surely move then. As I approached, I spoke to it. Still nothing. I passed behind it. Not a twitch, not a blink. I walked to the other side of the road and took another photo. Nothing from the horse. A few more photos and finally the horse flicked its tail, the first sign of life since I initially saw it. After a while, the horse gathered itself, turned around, and eased into the trees.
Later, on my return after going a little way up the Muliwai Trail, I took the trail which runs through the trees behind the beach. A short way along the trail I just got a certain feeling. I turned around and there was a horse following me only about 10 feet behind. I hadn’t seen it. I hadn’t heard it. It looked at me, then turned toward the ocean. I walked on a few paces, then looked back. The horse was gone, nowhere to be seen.
Waipi’o Valley with Hi’ilawe Falls in the distance, seen from a viewpoint on the Muliwai Trail which leads to Waimanu Valley.
Waipi’o beach seen from the overlook near the parking area.
The stream crossing to reach the far end of the beach and the Muliwai Trail.
The road down into Waipi’o Valley is rough, winding, and very steep.
There’s a 22 miles stretch of the northern Big Island coast, from Pololu to Waipi’o Valley, that isn’t accessible by car. At the southeast end of that stretch, the road ends at the Waipi’o Valley overlook. From there, a paved road descends into the valley. It’s rough, winding, and very steep. The average grade is 25%, steeper in places. Four-wheel drive and healthy brakes are a must.
The alternative is to hike into the valley, which is what I did. The road drops about 800 feet in just over half a mile. It’s hard on the knees, but easy on the eyes. There’s a gradual unfolding of details that aren’t visible from the overlook – fields, dwellings, horses. The valley, which is important in Hawaiian history, was wiped out in a 1946 tsunami. Now it’s populated by taro farmers and people who tend to shy from society. It’s a bit of a clash for it to be a popular tourist stop.
At the foot of the hill is a junction. The road continues straight on into the valley, but the public access soon ends. In the opposite direction the road heads to the sea. After a little under half a mile, the sandy, lake-filled road breaks out to the beach. There’s lots of parking under the trees. On the other side of them is the beach, a long, curved stretch of smooth sand, interrupted only by the ‘stream’ that has to be crossed to access the far end.
I can’t say where it’s best to cross this stream; conditions vary from day to day depending on the state of the tide and the flow of water. I waded out just inland of the furthest reaching waves. I felt my way across the rounded rocks underfoot, feeling reasonably pleased with my progress. But about three-quarters of the way across, I reached the fastest flow of water, which had also cut the deepest channel. It was probably only a couple of feet deep, but it required great care not to lose my footing. This fast-flowing channel was soon crossed and I hauled myself out, somewhat relieved, on the sand at the other side.
A deserted beach stretched out ahead. I strolled along the water’s edge and, at the far end, cut inland to find the Muliwai Trail, which leads to Waimanu Valley eight miles farther on. The trail is steep and narrow as it zigzags up the cliff. After a short while it breaks into the open and lovely views emerge, back the way I’d come and up the valley where there’s a good view of Hi’ilawe Falls. This was my turnaround point. The return across the stream was easier, knowing what was involved. The hike back up the road to the overlook a steady, sweaty haul, though I was surprised it only took me 10 minutes longer than the descent.
This sign greets visitors to Mo’okini heiau. The heiau dates back to the 11th or 12th Century when it was an important religious site where thousands of human sacrifices were carried out. A hazardous area indeed. I imagine there were many who would happily have risked climbing the walls in those days.
This is the time of year when silverswords bloom. These plants, members of the sunflower family, are endemic to Hawaii. There are slightly different silverswords growing on Mauna Loa, Mauna Kea and Haleakala on Maui. The plants are very susceptible to root disturbance and the activities of goats, pigs and humans has led to their decline. They’re making a comeback now thanks to fenced enclosures and careful management.
These photos were taken on Mauna Loa a few years back. The flower stalks were about 6 to 8 feet tall. The plants live for up to 30 years, but once they bloom, they die (like the one in the background of the top photo).
In the second photo, the ongoing eruption of Kilauea’s Pu’u O’o vent can be seen.
Graham's Island 